To listen for new IQ requests, add the appropriate entry in
jabber-iq-get-xmlns-alist or jabber-iq-set-xmlns-alist.
The key is the namespace of the request, and the value is a function
that takes one argument, the entire IQ stanza in list format.
jabber-process-iq reads these alists to determine which
function to call on incoming packets.
For example, the Ad-Hoc Commands module contains the following:
(add-to-list 'jabber-iq-set-xmlns-alist
(cons "http://jabber.org/protocol/commands" 'jabber-ahc-process))
To send a response to an IQ request, use (jabber-send-iq
sender "result" query nil nil nil nil id), where
query is the query in list format. jabber-send-iq will
encapsulate the query in an IQ packet with the specified id.
To return an error to the Jabber entity that sent the query, use
jabber-signal-error. The signal is caught by
jabber-process-iq, which takes care of sending the error.